[tex]1.\\dane:\\v_{o} = 0\\h = 4 \ m\\g = 10\frac{m}{s^{2}}\\szukane:\\v = ?\\\\Rozwiazanie\\\\Z \ zasady \ zachowania \ energii\\\\E_{p} =E_{k}\\\\mgh = \frac{mv^{2}}{2} \ \ /\cdot\frac{2}{m}\\\\v^{2}=2gh\\\\v = \sqrt{2gh}\\\\v = \sqrt{2\cdot10\frac{m}{s^{2}}\cdot4 \ m} = \sqrt{80}\frac{m}{s} = \sqrt{16\cdot5}\frac{m}{s} = 4\sqrt{5}\frac{m}{s}\\\\v \approx 8,94\frac{m}{s}[/tex]
[tex]2.\\dane:\\v_{o} = 2\frac{m}{s}\\h_{o} = 0,5 \ m\\g = 10\frac{m}{s^{2}}\\szukane:\\h = ?\\\\Rozwiazanie\\\\mgh_1 = \frac{mv_{o}^{2}}{2} \ \ /:mg\\\\h_1 = \frac{v_{o}^{2}}{2mg}\\\\h_1 = \frac{(2\frac{m}{s})^{2}}{2\cdot10\frac{m}{s^{2}}} = 0,2 \ m\\\\h = h_{o}+h_1\\\\h = 0,5 \ m + 0,2 \ m = 0,7 \ m[/tex]
